Onsite collection, temporary storage, and use of precipitation-generated runoff and other excess site water, e.g. from underdrain and sump pump discharges, stored in temporary water storage structures and cisterns have been used for a myriad of purposes for thousands of years. The potential benefits of these systems are increasingly of interest to regulators, water and sewer operators and managers, engineers, architects, and landscape architects involved in site and building design and, as such, are being integrated more and more into urban runoff management systems.
In many areas of the United States, onsite collection, storage, and use of excess site water and precipitation-generated runoff, which is referred to as “harvesting”, “rainwater harvesting” and/or “site water harvesting”, have seen increased integrated into new and existing construction as interest in resource conservation and sustainable building practices have expanded. Not insignificantly, the U.S. Environment Protection Agency (USEPA) in its 2008 Rainwater Harvesting Policies Handbook states that, “Rainwater harvesting has significant potential to provide environmental and economic benefits by reducing stormwater runoff and conserving potable water . . . .” However, despite the expansion of these practices there has been limited evaluation of methods for optimal control of these systems.
To achieve the full benefits of harvesting, one must maximize the availability of stored water for use while minimizing volume overflowing from or bypassing the storage system into downstream water bodies. Conventional practices tend to emphasize only one potential benefit, which is to say, either storm water management or water conservation, but not both, without considering the potential to optimize a system to address both benefits.
Moreover, current control systems do not include sophisticated control logic that addresses these limitations. Indeed, and most critically, existing systems rarely utilize network-based weather forecasting information in order to anticipate the likely volume of future precipitation, e.g., water or snowmelt, that may be added to the storage system during a future precipitation event or current precipitation being contemporaneously added to the storage system and act on this information in affecting the volume maintained in the storage structure.